"JJ" Johnston (far left) speaks about "microdynamics" at PNW Section February 2015 meeting held at Digipen. boB Gudgel photo.
What Is Microdynamics?
This is the question James D. (jj) Johnston presented to the group at the PNW Section February meeting, held at the Digipen Institute of Technology in Redmond, WA. He said it was neither Dynamic Range nor RMS; and loosely defined as "variation in loudness" based on an insufficient number of experiments. After a short review of terms (such as "loudness"), he presented some challenges of using dynamic range as a measure of microdynamics with some examples of number sequences that can "break" a dynamic range calculation. This was followed by the introduction of a Matlab/Octave script (lplt_t.m) that he wrote (and made available on the PNW Section website) that analyzes sound files based on a loudness model. The rest of the talk was spent looking at the results of different program material processed with the script, demonstrating how the various plots corresponded to audible effects in the material.
After the break and door prizes, Bob Smith gave a short presentation on how to install Octave (an open-source version of Matlab "matrix laboratory") with minimal pain, pointing out some of the pitfalls of the installation process.
